Plaster lath



Aug. 4, 1925. 1,548,538

Clo-hi2 E Malcounslci/ IN VEN TOR.

Q mm A TTORNEY UN I TE D S T A TE JOHN F. IMAKOWSKI, 0F STOCKTON, CALIFORNIA, ASSIGNOR T0 CALIFORNIA CEDAR PRODUCTS COMPANY, OF STOCKTON, CALIFORNIA.

PLASTER LATI-I.

Application filed May 31, 1923. Serial No. 642,498.

To all whom it may concern:

Be it known that I, JOHN F MAKOWSKI, a citizen of the United States, residing at Stockton, county of San Joaquin, State of California, have invented certain new and useful Improvements in Plaster Lath; and I do declare the following to be a full, clear, and exact description of the same, reference being had to the accompanying drawings, and to the characters of reference marked thereon which form a part of this application.

This invention relates to the building art and particularly to wall construction.

The present invention is designed to produce a strong, fire resisting and water proof lath for supporting plaster, cement or other plastic wall finishes and one which will be particularly adaptable for exterior use when a stucco finish or the like is desired.

The object of the invention is to produce an inexpensive lath which nevertheless will have the same or greater utility than those now produced. v

The scope and advantages of the invention will readily appear by a perusal of the following specification and claim.

In the drawings similar characters of reference indicate corresponding parts in the several views;

Fig. 1 is a fragmentary perspective view of one of my improved laths.

Fig. 2 is a cross section of an exterior por tion of a wall constructed with my improved lath.

Referring now more particularly to the characters of reference on the drawings, the numeral 1 designates a wooden board of any desired length and width, preferably 1% X2 I One pair of vertically alined edges of this board are provided with longitudinal dove tail grooves 2, the front edges of which stop short of the plane of the back or inner edges, or in other words are closer together than said back edges, so that when two boards are set on the wall edge to edge there will be an open space 3 leading into the adjacent dove tail grooves so that plastic material may flow into the same, whereupon such grooves act as a key to further the function of the lath as hereinafter set forth.

In making up my plaster lath I prepare a composition mixture l of one part magnesite to one and one half parts filling material such as fullers earth or other diatomaceous earth and to this I add a solution of magnesium chloride of from 18 to 20% strength to make the composition of a consistency which will readily spread over the front face of the board and into the grooves 2, as shown. This may be appliedto the surface of the board in any suitable manner.

While the magnesite composition is still soft I spread on the same, by suitable means, a quantity of small gravel or other suitable objects 5, the same having irregular contours and surfaces. hen the magnesite sets this gravel will be firmly and inseparably embedded therein, as the magnesite composition is a binder and adhesive.

The boards are treated as above before be ing applied to the studding, to which they are secured in close vertical alinement. The spaces or interstices back of and between the gravel particles form a mechanical key or look for the plaster, cement or other plastic material 6, which is then spread over the same. The gravel being a natural bond for lime, cement or the like, I have found that a very thin layer of the plastic may be spread over the same and at once set up into stucco or other finish and will hold firmly and with no likelihood of cracking, checking or falling off. The dove tail grooves 2 also aid materially in keying the plastic material to the wall, especially since the magnesite and gravel composition surface is followed around into such grooves.

The magnesite, being naturally impervious to moisture and a fire resistant, a wall con structed as shown and described will be of great value to the building industry.

To compensate for any possible warping of the boards and to tend to prevent them from moving apart at their edges with natural contraction, I provide rear longitudinal grooves 7 in the boards, suitably spaced apart.

Having thus described my invention what I claim as new and useful and desire to secure by Letters Patent is:

In a plaster lath comprising a board having grooves formed in parallel edges thereof and disposed so that when like boards are laidedge to edge, a longitudinal opening Will be formed leading to said grooves from one face of the boards to receive plastic ma- 5 terial; Water proofing material applied in the grooves and to the entire surfaces of the boards to which the plastic material is to be applied, and mechanical bonding material for said plastic disposed over tl1e surface of the boards and grooves over, and held by, 1 the Water proofing material.

In testimony whereof I aflix my signature.

JOHN F. MAKOWSKI. 

